The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Fuel cells produce electricity through an electrochemical reaction between hydrogen and oxygen. Fuel cells may continuously generate electric power upon receiving a chemical reactant from the outside, even without a separate charging process.
A fuel cell may be formed by disposing separators (or bipolar plates) on both sides of a membrane-electrode assembly (MEA) intervening therebetween. A plurality of fuel cells may be continuously arranged to form a fuel cell stack.
Here, a membrane-electrode assembly that is an example of a core component of the fuel cell as a three-layer structure, includes an electrolytic membrane in which hydrogen ions transfer, an anode catalyst electrode layer formed on one surface of the electrolytic membrane, and a cathode catalyst electrode layer formed on the other surface of the electrolytic membrane. A direct coating method and a decal method are examples of a method of manufacturing the three-layer structure membrane-electrode assembly.
Among them, in the case of the decal method, an electrode film coated with each catalyst electrode layer is deposited on both surfaces of the electrolyte membrane, the catalyst electrode layer is transferred to both surfaces of the electrolyte membrane to be joined, and then the electrode film is removed, thereby manufacturing the membrane-electrode assembly of a three-layer structure.
That is, in the manufacturing process of the membrane-electrode assembly using the decal method, an electrode film of a roll type coated with each catalyst electrode layer and an electrolyte membrane of a roll type pass a bonding roll of high temperature and high pressure to be laminated (thermally compressed), and the electrode film is removed to manufacture the membrane-electrode assembly of the three-layer structure.
As described above, in the process of manufacturing the membrane-electrode assembly of the three-layer structure by the decal method using the roll laminating process, there are advantages in production with glass since a manufacturing speed may be improved.
However, in the decal method using the roll lamination process, in the state that the electrode film coated with each catalyst electrode layer on both sides of the electrolyte membrane interposed therebetween is positioned, since they pass between the bonding rolls of high temperature and high pressure and the catalyst electrode layer and the electrolyte membrane are laminated in the directions such that they contact each other, we have discovered that it is difficult to align the lamination positions of the anode catalyst electrode layer and the cathode catalyst electrode layer.
That is, the electrode film and the electrolyte membrane continuously pass between the bonding rolls of high temperature and high pressure that are pressed and the catalyst electrode layer is laminated on both surfaces of the electrolyte membrane, and in this roll laminating continuous process, we have discovered that it is difficult to correctly accord the lamination positions of the catalyst electrode layers by a feeding speed difference of the electrode film.
We have further discovered that the lamination positions of the anode catalyst electrode layer and the cathode catalyst electrode layer are difficult to align because a pitch between the catalyst electrode layers is not constant in the process of manufacturing the catalyst electrode layer of the continuous patterns by coating the catalyst slurry to the electrode film.